Drill guide



Dec. 48, 1953 N. L. WARD 2,661,633

DRILL GUIDE Filed Aug. 30, 1950 3 Sheets-Sheet l Nathan L. Ward INVENTOR.

Dec. 8, 1953 N. L. WARD 2,561,638

DRILL GUIDE Filed Aug. 30, 1950 5 Sheets-Sheet 2 INVENTOR.

N. L. WARD DRILL GUIDE Dec. 8, 1953 3 Sheets-Sheet 3 Filed Aug. 30, 1950 Nathan L. Word INVENTOR.

Patented Dec. 8, 1953 UNITED STATES: PATENT OFFICE 2,661,638 DRILL GUIDE Nathan 1.. Ward, Reynolds, Ina. Application August so, 1950, Serial No, 182,223

(c1. w 1s {Claims 1 This invention comprises novel and useful im provements in a drill guide and more specifically pertains to a drill guide centering attachment specifically adapted formounting upon the spindles of lathes and similar machines to facilitate the drilling of center holes in rods, shafts, or like members.

The primary object of this invention is to provide a centering attachment for the spindles of lathes and similar machines which shall be capable of accurately and easily centering work and facilitating the drilling of centerholes therein.

A further object of the invention is to provide an attachment as set forth in the preceding object which may be detachably secured to the spindle of a lathe or similar machine in an improved and easily applied or removed manner.

Yet another object of the invention is to provide an attachment forlathes or the like, as set forth in the foregoing objects, in which the mounting means is utilized for supporting a center drill by the lathe spindle.

These, together with various ancillary features and objects of the invention which will later become apparent as the following description proceeds, are attained by the present invention, preferred embodiments of which have been illustrated, by way of example only, in the accompanying drawings, wherein:

Figure 1 is a vertical central longitudinal sectional view through a portion of a lathe spindle to which one form of attachment, in accordance with the principles of this invention, has been applied; v

Figure 2 is a view similarto Figure 1 but showing a modified form'of attachment applied to the spindle of a lathe;

Figures 3' and 4 are, respectively, endj'views of the attachments of Figures 1 and 2, taken from the left end of these' figures'; i

Figure 5 is a verticaltransverse sectional view taken substantially vuponthe plane indic'atedby the section line 550f'Figu're 1;

Figure 6 is 'a'vertical transverse sectional view taken'substantially upon the plane "indicated by.

the section 1ine"6-' -6 of "Figure '2; and

Figure 7 is a vertical transverse sectional view taken substantially upon the plane indicated by the section line 1 1:br Figure 1.

In order to fully comprehend the underlying principles of this invention, the means. by which the principles may be suitably realized and the advantages accruing or rising'therefrom, it should be noted theta, fundamental and very important operation of machinists utilizingmetal working equipment such as lathes, or the'like, and regardless of whether these'machinists are amateur machinists utiliz'inglthe' relatively simple equipment of home work shops: and the like or in dustrial machinists employing'complex' and re fined precision and power machinery, it is the operation of drilling center holes in shafts, rods, or other elongated bodies as aprelude to themounting of these bodies lathes or similar tools for the performance of other metal working operation to be performed.

Referring now more si c a -r ,to-t a companying drawings, wherein like numerals =desig-, Hate ar Parts throushQut-th rio s i attention is directed first to the embodiment of theinvention illustrated in ljigures 1, 3, 5 and'fi.

In this somewhat simplified;embodiment, according to the principles ofthis invention,-the numeral l0 designates a lathe spindle which is provided with the customary internally tapered bore l2 The tailstock of the lathe-in which the spindle islongitudinally movable as by means of;

a suitable hand wheel gnot -shb wn) I is indicated by the numeral ii. The attachment illustrated in this embodimentwhich 'isadapted t be re movably supported by thespindle 10 consists of a supporting frame-l4 which; as shown in Figure .7, comprises a' pair-of; integral arms which merge into a -hub portion =1 6 having an internally tapered bore -l8.- The,-hub;li6is provided-with an externally threaded portion-20 fora purpose which will later be set forth:

An arbor22 is provided having one end provided with an e rternallyrtapered:portion-=-2 3 adapted to be frictionally received in the inter nally tapered bore 12 ofthe spindle-l0 ;-and=having its other end externally tapered, asat 26,"

for reception in the internally -tapere'd bore 1-8 of the hub portion 16. As-will nowbe apparent,

the arbor will be placed in the spindle -l 0; and the hub portion; I6 pf the -supporting-:frame 1| 4 leasably clamped at any desired position upon, the exterior surface of the spindle H3. The sleeve 7 28 extends beyond the end of the spindle ID, and is provided with an annular groove 3 adapted to receive an annular ring or key 2-5 which may I U be segmental if desired. This ring or key is further seated in an annular groove 38 formed in the fastening nut 40 which is thus slidabl'e upon the split sleeve 28 between the ring or key 36 and an enlarged headed portion 32 at the opposite end of the split sleeve.

As will now be readily apparent, the split sleeve may be adjustably clamped upon the spindle in any desired position, and with the arbor 22 received within the spindle bore, the attachment is placed upon the arbor and the fastening nut 40 serves to tightly lock the end of the hub [6 of the attachment against the end of the split sleeve 28 and to hold the hub tightly upon the arbor 22.

It will thus be seen that the attachment is rigidly and firmly secured to the spindle of the lathe or other machine with which the attachment is to be employed.

With further reference to. Figure 1, it will be seen that the arbor is provided with an internally tapered bore 44 disposed at its outward end, which bore is adapted to receive the correspondingly tapered shank 4B of a center drill bit 48. The drill bit shank is further provided with a key portion 50 received in a corresponding slot or recess in the end wall of the bore 44 which thereby prevents rotation of the center drill bit with respect to the arbor.

The arbor is further provided with an internally threaded passage 52 which extends axially of the arbor, intersects the recess or slot receiving the portion 59 of the shank of the drill bit, and opens through the other or inner end of the arbor. An adjusting screw 5A is received in the passage 52 and is adapted to engage the end of the shank portion 50 for forcing the drill bit from its tapered socket 44. For this purpose, the screw 54 is provided with a head portion 55 which extends exteriorly of the inner end of the arbor, and in some instances by merely moving the lathe sleeve Id inwardly, the head 56 may be utilized to push the arbor 22 from the spindle.

Referring now again to the supporting frame I4, it will be seen that the outer end of the two arms of the same are provided with a face plate or annular ring 58. Carried by the supporting frame I4 is an axially extending sleeve (it which may be press-fitted or otherwise rigidly and immovably attached to the supporting frame in a suitable annular seat 62 within the face plate 58 and within the ends of the arms of the support frame. 7

The outer surface of the face plate 58 is provided with suitable radially disposed guideways 64 in which are received a plurality of jaws 66.

As illustrated in Figures 1 and 2, the guideways 54' are extended through the axial sleeve 69 so that the jaws may be movable radially through tions to be performed by the machine with which the supporting frame, the base plate 58 thereof, and through the sleeve 60 into the interior of the sleeve for engaging and rotatably supporting the work piece which is to be center drilled.

However, in some instances, it may be preferred to terminate the inner end of the sleeve 60 on the outer faces of the jaw 65, so that the jaws will be slidable only through the guideway 64 of the face plate 58. However, the construction illustrated is deemed to be preferable as regards strength and area of guiding surface for the jaws.

It evident that any desired number of jaws may be provided in accordance with the type of work to be carried and the nature of the operai .the device is attached. For light work, a relatively small number of jaws, such as three equally spaced jaws, could be provided, while for heavy work a large number of jaws, such as five, would be deemed preferable. The embodiment of Figure 1, while not limited thereto, therefore illustrates an attachment for a lighter type of work, including three mounting jaws, while the embodiment of Figures 2, 4, and 6 illustrates a heavyduty attachment having five jaws.

The outer faces of the jaws 8t are provided with rack teeth 68 which are adapted to engage the corresponding involute tracks iii on the' adjacent face of the scroll plate 12.

This scroll plate is provided with an axial bearing surface M whereby the latter may be rotatably journaled upon the exterior surface of thesleeve 68 and simultaneously move all of the jaws 66 towards or from the axis or line of centers of the lathe or other tool.

In order to maintain the jaws and scrollplate in their adjusted positions, a locking means is provided. This locking means includes external screw threads 18 formed upon the exterior outer surface of the sleeve til, together with a longi tudinally extending keyway 5: cut into these threads for receiving a keyed projection iii of a A fastening nut 82 is screw.

lock' washer 8H. threadedly engaged upon the threads 78 of the sleeve 60 and is provided with axially extending. It will now be. ap-.-.

finger grip projections 84. parent that the scroll plate, together with the jaws may be locked in their adjusted position by merely rotating the'fastening nut 84 to cause the non-rotatable lock washer 8i} to press against the scroll plate, thereby pressing the scroll plate. against the jaws and the latter against their.

guideways in the face plate 58.

7 If deemed desirable, the inner ends of one or more of the jaws as may be provided withantifriction rollers, one ,of' which is indicated in Figure 1 at 26.

held in the lathe chuck (not shown) of the. lathe; the other end of the work pieceis disposed within the center drill guide frame I i and is clamped In operation, these .rollers will. center and rotatably support the pieceof workv One end therein by the jaws 66. The jaws on the lathe chuck (not shown) are then tightened on the end of the work piece held therein. After this tightening, the jaws it on the frame M are adjusted so that the end of the Work piece disposed therein is centered but permitted to turn freely and these jaws and the work piece adjacent thereto are lubricated. The lathe is then started and the work piece rotated. As the work piece is rotated, the tail stock hand wheel (not shown) is operated forcing the spindle I9 out and causing the drill guide frame M to move longitudinally along the work piece. Upon such longitudinal movement of the drill guide frame, the drill bit 48 penetrates the end of the work piece and center drills the same.

Reference is now made to what has been previously termed the heavy-duty attachment of Figures 2, 4, and 6. This construction is identical with that previously described as regards the lathe center, the supporting arbor, the center drill, the split clamp and the mounting of the same upon the spindle, the supporting frame of the attachment, the axial sleeve, and the movable jaw construction previously described, and consequently these parts are provided with the same numerals employed in the description of the preceding embodiment. This latter embodiment, however, difiers from that previously described chiefly in the aforementioned increase in the number of jaws in order to enable the device to accommodate greater loads during operation; and by replacing the previously described manual adjusting projection it of the scroll plate 72 with a gearing assembly for rotatably adjusting the scroll plate. For that purpose, it will be apparent that the scroll plate I2 is provided with a bevel gear 99 which is continuously in mesh with and is engaged by the pinion 92 having a shaft 94 which is rotatably journaled in a supporting bracket 96 mounted upon one of the arms of the frame 14 as by fastening bolts 98.

Moreover, it is preferred in this embodiment to provide all of the jaws with the above mentioned anti-friction rollers 86.

Since, from the foregoing, the construction and advantages of this drill guide are readily apparent, further description is believed to be unnecessary.

However, since numerous modifications and equivalents will readily occur to those skilled in the art after a consideration of the foregoing specification and accompanying drawings, it is not intended to limit the invention to the exact embodiment shown and described, but all suitable modifications and equivalents may be resorted to which fall within the scope of the appended claims.

Having described claimed as new is:

1. A drill center guide attachment for lathes the invention, what is comprising a supporting frame, means for mounting said frame upon the spindle of a lathe, a split sleeve clampingly engageable upon a lathe spindle, a fastening nut slidable upon said split sleeve, complementary annular grooves in said split sleeve and said fastening nut, locking ring segments seated in said annular grooves, an externally threaded hub on said frame engageable by said fastening nut.

2. A drill center guide attachment for lathes comprising a supporting frame, means for mounting said frame upon the spindle of a lathe, said mounting means including an arbor having one end tapered to engage the internal taper of a lathe spindle and having its other end tapered for receiving thereon an internally tapered bore in said frame, a split sleeve clampingly engageable upon a lathe spindle, a fastening nut slidable upon said split sleeve, complementary annular grooves in said split sleeve and said fastening nut, locking ring segments seated in said annular grooves, an externally threaded hub on said frame engageable by said fastening nut.

3. A drill center guide attachment for lathes comprising a supporting frame, means for mounting said frame upon the spindle of a lathe, said means comprising a sleeve engaged upon the lathe spindle, a fastening nut slidable upon said split sleeve, complementary annular grooves in said sleeve and said fastening nut, locking ring segments seated in said annular grooves and an externally threaded hub on said frame engaged by said fastening nut.

4. A drill center guide attachment for lathes comprising a supporting frame, means for mounting said frame upon a lathe spindle, said mounting means comprising a split sleeve clampingly engageable on a lathe spindle, a fastening nut slidable on said split sleeve, complementary annular grooves in said split sleeve and said fastening nut, locking ring segments seated in said annular grooves, an externally threaded hub on said frame engageable by said fastening nut, said hub having an open ended axial bore therethrough, an arbor disposed in said bore having a portion thereof engaged in the lathe spindle, a drill bit mounted in said arbor and extending axially into said supporting frame.

NATHAN L. WARD.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 50,691 Cushman Oct. 31, 1865 166,538 Mason Aug. 10, 1875 313,562 Watson Mar. 10, 1885 666,753 Hamilton Jan. 29, 1901 771,709 Carney Oct. 4;, 1904 1,264,429 Nossagk Apr. 30, 1918 1,309,217 Ratheram July 18, 1919 1,870,350 Van Norman Aug. 9, 1932 

